Certain beverage preparation machines use capsules containing ingredients to be extracted or to be dissolved; for other machines, the ingredients are stored and dosed automatically in the machine or else are added at the time of preparation of the drink.
Most beverage machines possess within a housing: filling means that include a pump for liquid, usually water, which pumps the liquid from a source of water that is cold or indeed heated through heating means, such as a heating resistor, a thermoblock or the like, a brewing unit in which an ingredient is brewed with water or a mixing unit in which ingredients are mixed together, and a beverage outlet for dispensing the prepared beverage. Examples of fluid circuits are disclosed in U.S. Pat. Nos. 2,715,868, 5,392,694, 5,943,472, 5,992,298, 6,554,588, WO 2006/032599, WO 2009/024500, WO 2009/150030 and WO 2010/006953.
Usually, the beverage outlet is located above a grid for supporting a cup or other recipient under the outlet and for the passage of possible drips from the beverage outlet or other spills into a collector tray located under the grid. Examples of such machines are disclosed in EP 0 549 887, EP 1 440 639, EP 1 731 065, EP 1 867 260, U.S. Pat. No. 5,161,455, U.S. Pat. No. 5,353,692, WO 2009/074557, WO 2009/074559, WO 2009/135869, WO 2011/154492 and WO 2012/007313.
Typically, beverage machines include vibrating devices such as pumps that tend to generate and propagate vibrations through the machines during use. Depending on the construction of the machine and its natural or resonant frequencies the noise and discomfort created by such vibration during use may be quite significant. It may be possible to adjust the overall natural or resonant frequencies of the machine, e.g. by adjusting the mass and/or structure of the machine. However, such an approach is rendered more difficult when the same vibrating devices can operate at different frequencies, e.g. a solenoid pump powered by a 50 or 60 Hz power supply 240 or 110 Volts depending on the place of use, or when the machine carries a variable mass, e.g. when the machine can carry different types of cups or mugs for filling thereof or when the machine is fitted with one or more reservoirs for fresh and/or waste ingredients that may be more or less filled during use. In such a case it is more difficult to prevent—over the entire possible range of use of the machine—the echoing of vibrations that are in line or close to the overall natural or resonant frequencies of the system, which may even result in vibration amplifications.
To reduce the nuisance caused by small movements of a beverage machine during use, in particular by vibrating parts of the beverage machine, typically pumps e.g. piston pumps, it is known to use dampening arrangements, e.g. by dampening the pump itself in the machine or by dampening the vibrations carried by the liquid pumped by the pump. Typically, a vibrating pump can be mounted in a beverage machine with specific vibration-dampening connectors, e.g. spring elements, as for instance disclosed in WO 2006/032599, WO 2009/150030 and WO 2010/108700. When a vibrating pump is used that transfers vibrations along the fluid line, the fluid circuit may include an arrangement for dampening the circulating liquid in the fluid line, e.g. such a fluid line may include elastic sealing connectors or membranes, as for instance disclosed in WO 2009/130099, WO 2010/006953, WO 2011/083103 and WO 2011/107574.
Despite the abovementioned efforts, there is still a need to reduce the nuisance and noise generated by small movements of beverage preparation machines during use, in particular due to vibrating parts of the machines.